Millions of householders are being duped when making donations to door-to-door charity bag collectors, it is claimed today.

Only a third of items donated stand a chance of ending up in high-street charity shops, with most items sold abroad for private profit, according to research by the British Heart Foundation (BHF).

Many charities, often those without shops, do deals with commercial firms who collect for them with bags emblazoned with the charity logo. But the company keeps all the donated goods and then re-sells them for profit, mostly to overseas markets.

They then make a royalty payment to the charity, but as little as five per cent of the cash made goes back to good causes, according to the BHF.

In some cases, charities are getting as little as £50 to £100 per tonne of goods collected when, in fact, the goods can sell abroad for anything up to £1,800.